Thomas Boulsover, a Sheffield cutler, invented the process wich became called Sheffield plate about
1740.
The date is uncertain because no patent was taken out. The next known manufacturer was Joseph Hancock,
in 1755, but others also began and in 1784 the Sheffield Plate makers obtained an Act of the Parliament
legalizing a mark consisting of the full name of the maker and an associated device. In Sheffield plate a
sheet of silver is fused on to a thicker one of copper and the compound billet rolled, both metals expanding equally,
become a thin sheet of copper coated with a layer of silver. About 1840 the Electroplate process superseded
Sheffielf Plate. Its production ceased about 1860.

Mark registered at the Sheffield Assay Office, under the regulations of the Act of 1784,
by makers of fused-plate and close-plated wares.
Those engaged in close-plating are indicated by three asterisks ***